Just got the PDFs today and have read through them, basically just once each. Here are some first impressions.

Mismatched flavor

One of the great strengths of Apocalypse World is that there is a lot of flavor built right into the names of the mechanical words used in the game. Cool, Hard, Hot, Weird, Sharp communicate not only mechanical things, but also add a lot of style. So far, I'm missing that in some things in Dark Age. The stat names don't really accomplish this dual purpose for me. I've played Apocalypse World, so I know what these things are, but they're not as instantly intuitive in this setting, and I feel like they're actually at cross-purposes with the style of the rest of the writing.

Another sort of separate example are a lot of the end states. In Apocalypse World, I felt like a really good case was made for the reward that retiring a character into safety would be, and it fits the existing fiction. That's what we want for Max, after all... That's the central struggle in The Walking Dead... But I don't know if it fits the Dark Ages as much. When I'm reading Joe Abercrombie or whatever, is that what I'm yearning for? Is that what I want for Conan?

Player overhead and complexity

Something I've noticed reading through the playbooks is a feeling of much more overhead for the players, as compared to Apocalypse World. I think that most of it is because of the increased emphasis on followers as a core part of a character. To me this is both a good thing and a bad thing. I know my players pretty well at this point. For some of them, the idea of managing followers and land and a holding and stuff is really awesome and cool. For some of them, making up a name for any NPC that follows them around would be a big chore. I fall into the former camp, but as the guy who does the GMing 90% of the time, I'd worry about a lack of interest from the latter group if I wanted to pitch this game to them.

It also adds time and complexity to character creation, at least as far as I can tell without actually playing it. In terms of sheer verbiage, Dark Age is definitely bigger than AW. There are some playbooks in vanilla AW with a little more overhead, but generally it's pretty simple, and the playbooks walk you through each step. It typically hasn't taken my players very many minutes to get into an AW playbook. I had my greatest success of my gaming career with AW in which I introduced two ladies (including my wife) who had never played any sort of hobbyist game of any sort before to RPGs, and I credit a lot of that with the simplicity of the system. I feel like the addition of followers as a major part, and a general feeling of additional complexity (rank, fortunes, fate, oaths, etc) would have made it a harder sell.

Another random effect from this was that the playbooks felt a teensy bit more samey to me than the ones from AW. In AW, it's mainly the hardholder whose deal is having followers and a war band and stuff, and that's part of what makes that playbook unique. Here, everybody gets some sort of follower.

Maybe this will be solved with some of the still-to-come playbooks?

More setting?

I'm sure this is by design, because the Dark Ages were a product of a specific set of circumstances, but it seems like there's a lot more setting built into Dark Age. To be clear, I'm definitely down with that, but it's very different to the seasoned AW player. In AW, I can get down with the fact that the setting is basically two sentences, and you come up with the rest on your own. You're forced to, in a way, and I think that's what makes it work so well. If you don't come up with some setting, you have no setting. In Dark Age, so far, it seems like I'm just getting teased. "Empire of Eagles"? That's fucking cool! I want to know more about this empire. I don't need to get into Forgotten Realms boxed set level detail, and I wouldn't want that, I just want some more cool hints. I've always thought that one of DVB's awesome strengths as a game designer is that he's mastered the art of the juicy hint. This could even be an optional sort of addendum chapter, like "rumors" or something, that you could throw in if your players want some more enticement.

Combat

I guess I could have lumped this in up above, but I do feel like reading through the go into battle section, I'm even more confused than I was when I read about going aggro the first time. I think that this would probably be solved with maybe less text right off the bat, and a whole shitton of examples that cover any situation that we've seen in our years of playing AW, and maybe that's the plan for the eventual final publication. Right now, I could probably really study that part and work with it in play, but it's not simple or clean to me yet.

Other stuff

I want to play this game. I'm really stoked for more, and while my group has been lulling around in this occasional Numenera campaign that I keep feeling like isn't as fun as it should be, this thing really makes me want to put in that awful effort to schedule a regular session. That's high praise! That effort is truly the worst (and I would love some sort of specific language about dealing with a game where different people can't make it from week to week, with tips on how to structure your thing so that works out most of the time...).

The only playbook that really didn't grab me was the War Herald, maybe because he felt a little familiar from Apocalypse World, but that's okay. I'm just one dude and I could see at least one of my players being really stoked to play him.

In general, I do feel like there's a lot more text than Apocalypse World. I'm pretty confident that's just due to the timing of these PDFs, but the first time I read AW I was like "holy crap, this is so simple and sleek and sexy and cool." Here I'm kind of a little more in my default RPG state, where I'm like, "okay, there's some stuff to absorb here, and I'm sure that once I get it in play, it'll be second nature."